How can I find constituents created from Tell-a-Friends

I've had a large amount of registrations that seem like spam from Tell-a-Friend messages. All of them have Tell-a-Friend in their profile. I need to find out when this started and remove them.

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Number:108261

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Luminate_Online

Constituent accounts created by the Tell-a-Friend feature will have an Origin Application Type of Tell-a-friend.Locating these constituents can be done by creating a query. To find when they were created, an "and" field clause must be added to your query using the Creation Time field.